一、代码如下：
Vector3 screenPos = Input.mousePosition;
screenPos.z = 5.0f;
Vector3 p1 = Camera.main.ScreenToWorldPoint(screenPos);
Vector3 p0 = Camera.main.transform.position;
float h2 = 0.0f - p0.z;
float h1 = p1.z - p0.z;
Vector3 dir = p1 - p0;
dir.z = 0.0f;
float d1 = dir.magnitude;
float d2 = d1 * h2 / h1;
Vector3 p2 = p0 + dir.normalized * d2;
p2.z = 0;
二、原理
三、项目应用场景
鼠标在屏幕上点击某一块网格，将点击后的屏幕坐标返回世界坐标，返回了世界坐标我们才能在画布中显示对应的功能
private void Update()
{
if(Input.GetMouseButtonDown(0))
{
Debug.Log("返回的点"+GetGridPointByMouse());
}
}
public Vector2 GetGridPointByMouse()
{
Vector3 screenPos = Input.mousePosition;
screenPos.z = 5.0f;
Vector3 p1 = Camera.main.ScreenToWorldPoint(screenPos);
Vector3 p0 = Camera.main.transform.position;
float h2 = 0.0f - p0.z;
float h1 = p1.z - p0.z;
Vector3 dir = p1 - p0;
dir.z = 0.0f;
float d1 = dir.magnitude;
float d2 = d1 * h2 / h1;
Vector3 p2 = p0 + dir.normalized * d2;
p2.z = 0;
return GetGridPointByWorldPos(p2);
}
public Vector2 GetGridPointByWorldPos(Vector2 worldPos)
{
float dis = 1000000;//起初记录一个最大值，保证可以进入循坏，后期可以进行再次改变
Vector2 point = new Vector2(); //point用来记录最终要返回网格点
for (int i = 0; i < gridList.Count; i++)
{
if (Vector2.Distance(worldPos, gridList[i].Position) < dis)
{
dis = Vector2.Distance(worldPos, gridList[i].Position);
point = gridList[i].Position;
}
}
return point;
}
直接到转化后的世界坐标p2进行传入或者处理即可。
